San Mateo County Weather in April
Average highs run from 61°F on April 1 to 61°F on April 30, and lows from 44°F to 46°F. Normal precipitation for the month is 1.81 in over about 9 wet days.
April day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
April at a glance
- Average high
- 61°F
- Average low
- 45°F
- Precipitation
- 1.81 in
- Record high
- 96°FApr 29, 1981
- Record low
- 31°FApr 3, 1931
- Chance of a freeze
- 5%
- Daylight
- 12 h 37 min to 13 h 44 min
- Cloud cover
- 55%
- Humidity
- 84%
- Dew point
- 48°F
- Wind
- 11.2 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation.
| Date | Normal high | Normal low | Record high | Record low | Chance wet |
|---|---|---|---|---|---|
| Apr 1 | 61°F | 44°F | 84°F 1959 | 33°F 1932 | 37% |
| Apr 2 | 61°F | 44°F | 88°F 1961 | 32°F 1931 | 37% |
| Apr 3 | 61°F | 44°F | 88°F 1961 | 31°F 1931 | 37% |
| Apr 4 | 61°F | 44°F | 86°F 1960 | 36°F 1945 | 36% |
| Apr 5 | 61°F | 44°F | 87°F 1989 | 36°F 1945 | 36% |
| Apr 6 | 61°F | 44°F | 90°F 1989 | 35°F 1975 | 35% |
| Apr 7 | 61°F | 44°F | 92°F 1989 | 33°F 1932 | 35% |
| Apr 8 | 61°F | 44°F | 92°F 1989 | 35°F 1932 | 35% |
| Apr 9 | 61°F | 44°F | 93°F 1989 | 31°F 1933 | 34% |
| Apr 10 | 61°F | 44°F | 90°F 1988 | 32°F 1933 | 34% |
| Apr 11 | 61°F | 44°F | 88°F 1988 | 36°F 1933 | 33% |
| Apr 12 | 61°F | 44°F | 87°F 1940 | 34°F 1956 | 33% |
| Apr 13 | 61°F | 44°F | 88°F 1947 | 37°F 1983 | 32% |
| Apr 14 | 61°F | 44°F | 90°F 1947 | 34°F 1931 | 32% |
| Apr 15 | 61°F | 45°F | 89°F 1966 | 33°F 1932 | 31% |
| Apr 16 | 61°F | 45°F | 90°F 1966 | 36°F 1955 | 31% |
| Apr 17 | 61°F | 45°F | 86°F 1954 | 35°F 1933 | 30% |
| Apr 18 | 61°F | 45°F | 89°F 2016 | 31°F 1933 | 30% |
| Apr 19 | 61°F | 45°F | 87°F 1950 | 36°F 1933 | 29% |
| Apr 20 | 61°F | 45°F | 93°F 1931 | 37°F 1972 | 28% |
| Apr 21 | 61°F | 45°F | 89°F 1931 | 35°F 1968 | 28% |
| Apr 22 | 61°F | 45°F | 89°F 2013 | 34°F 1932 | 27% |
| Apr 23 | 61°F | 45°F | 90°F 1946 | 36°F 1937 | 27% |
| Apr 24 | 61°F | 45°F | 88°F 2019 | 36°F 1964 | 27% |
| Apr 25 | 61°F | 45°F | 89°F 2004 | 37°F 1964 | 26% |
| Apr 26 | 61°F | 46°F | 94°F 2004 | 35°F 1932 | 26% |
| Apr 27 | 61°F | 46°F | 92°F 2004 | 36°F 1955 | 25% |
| Apr 28 | 61°F | 46°F | 93°F 1981 | 38°F 1950 | 25% |
| Apr 29 | 61°F | 46°F | 96°F 1981 | 36°F 1937 | 25% |
| Apr 30 | 61°F | 46°F | 93°F 1981 | 36°F 1937 | 25% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (PDT).
- April 1
- sunrise 6:55 AM, sunset 7:32 PM
- April 30
- sunrise 6:15 AM, sunset 7:59 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00043714 (Half Moon Bay), public domain. Records: NOAA GHCN-Daily, station USC00047339, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.